Related by context. Frequent words. (Click for all words.) 60 Soil erosion 59 salination 58 salinization 58 groundwater depletion 57 hydrologic cycle 57 Melting glaciers 55 temperate forests 55 soil salinity 54 nitrogen deposition 53 drier summers 53 receding glaciers 53 wetland ecosystems 53 icecaps 52 terrestrial ecosystems 52 wetter winters 52 severe droughts 52 plankton blooms 52 tropopause 52 freshwater habitats 52 riparian zones 52 Migrating birds 52 hydrological cycle 52 deltaic 52 acidify 51 temperature gradients 51 freshwaters 51 glaciers melt 51 upper troposphere 51 Poyang Lake 51 Algae blooms 51 coniferous forests 51 upwellings 51 species extinctions 51 phytoplankton blooms 51 lakeshores 51 Warming temperatures 50 seabeds 50 habitat fragmentation 50 nesting habitats 50 freshwater ecosystems 50 Sea otters 50 subglacial 50 glacial melt 50 reactive nitrogen 50 river deltas 49 population densities 49 warmer wetter 49 streambanks 49 ecologies 49 prolonged droughts 49 Wadden Sea 49 recharge groundwater 49 poleward 49 drylands 49 deplete oxygen 49 Rapid urbanization 49 glacier melt 49 deciduous forests 49 acidifying 49 hotter drier 49 hotter summers 49 arable farmland 49 gyres 48 ozone layer depletion 48 salinity 48 Severe drought 48 glacial retreat 48 Polar Regions 48 soil erosion 48 nutrient loading 48 ecosystems 48 migratory bird populations 48 thawing permafrost 48 Tibetan Plateau 48 coastland 48 aquatic habitats 48 Unseasonably warm 48 ocean acidity 48 frequent droughts 48 Northerly winds 48 periodic droughts 48 groundwater aquifers 48 subarctic 48 aquatic ecosystem 48 inter tidal 48 glacial melting 48 biogeochemical 48 refugia 48 pollutions 47 earthquakes volcanoes 47 temperature inversions 47 lake sediments 47 escarpments 47 moist soils 47 Volcanic eruptions 47 Acidity 47 reedbeds 47 colder winters 47 melting permafrost 47 temperate rainforest 47 riparian vegetation